Magnetic filters have been used to remove magnetic contaminants from industrial process streams. For example, U.S. Pat. No. 8,506,820 to Yen et al. and U.S. Pat. No. 8,636,907 to Lin et al. describe filters having removable permanent magnetic bars that are disposed within non-magnetic sleeves. During the filtration process, magnetic contaminants adhere onto the external surfaces of the sleeves. The contaminants disengage from the sleeves once the permanents magnetic bars are removed from the sleeves. Prior art devices also employ metal matrices that are magnetized by magnetic fields produced by an external electromagnetic coil as exemplified by U.S. Pat. No. 3,539,509 to Heitmann et al., U.S. Pat. No. 3,873,448 to Isberg et al., U.S. Pat. No. 4,594,160 to Heitmann et al, U.S. Pat. No. 4,722,788 to Nakamura, and U.S. Pat. No. 5,766,450 to Herman et al. Prior art magnetic filters with metal matrices are deficient in that the filters are low capacity with uneven contaminant capture and accumulation across the matrix.